The Benchmark Assessment asked this:

Which of the following statements explains why recycled plastics must be separated by their recycling code?
A: The six different recycling codes represent polymers made of long chains of repeating clusters of atoms, called monomers.
B: The six different recycling codes represent different isotopes with varying degrees of nuclear stability.
C: The six different recycling codes represent different elements on the periodic table.
D: The six different recycling codes represent different macromolecules with no elements in common with each other.
How did you arrive at your answer?

The Following Answers Were Awarded No Credit. Can you tell why?